Enabling Ssh Authentication Using Ssh Keys - D-Link NetDefendOS User Manual

• Interface: lan
• Network: lannet
4. Click OK
Automatic Authentication with SSH Keys
By default, SSH access requires a username and password to be entered. An alternative is to
authenticate automatically by using SSH keys. This method of authentication is useful when using
scripts.
Authentication in this way requires that the public key file of a public/private key pair is
uploaded to NetDefendOS and associated with the relevant User object. Both the public and
private key files are installed in the connecting SSH client.
SSH key authentication is enabled with the following steps:
1. Create a suitable set of key files using a third party tool. Key generation can also be done
directly within some SSH clients. The key files will consist of a private key file and a public
key file. By convention, these are often called id_rsa (the private key) and id_rsa.pub (the
public key).
2. Install the key files into the SSH client. This may already have been done if the client was
used to generate the keys.
3. Upload the public key file to NetDefendOS using SCP. The file must be stored in the
NetDefendOS folder called sshclientkeys (SCP and this folder are described further in
Section 2.1.7, "Secure Copy").
The public key file will usually have an original filetype of .pub but the filename on
NetDefendOS cannot have a period (".") in the name. If the local filename of the certificate's
public key file is id_rsa.pub, this must become something without the period in
NetDefendOS storage. For example, it could get the new name my_public_ssh_key and it
might be uploaded to NetDefendOS with an SCP client command similar to the following:
> scp id_rsa.pub admin@203.0.113.5:sshclientkeys/my_public_ssh_key
4. In NetDefendOS, set the SSH Keys property of the relevant User object to be the uploaded
public key file. For example, the user admin could be assigned the key file
my_public_ssh_key. This step is described in detail in the example below.
5. Connect to NetDefendOS using SSH with key authentication. Authentication will now occur
automatically and there will be no prompt for credentials to be entered.
Example 2.8. Enabling SSH Authentication Using SSH Keys
This example shows how to enable automatic SSH authentication for the user admin. It is
assumed that an SSH public key file called my_ssh_cert has already been uploaded to
NetDefendOS's sshclientkeys folder using SCP.
Command-Line Interface
Chapter 2: Management and Maintenance
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